A quadratic problem

if $f(x) = (3x^{3c-9}+2)^2$ is a quadratic function, what is $c$ ?

#Algebra

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Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
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`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
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Comments

I'm not sure but I think c = $\frac { 10 }{ 3 }$ because a quadratic function should be in a form of $f\left( x \right) =a{ x }^{ 2 }+bx+c$ and if the exponent of 3x is not 1 then if you square the expression, the result will not be a quadratic function so it should be 1

$3c-9=1\\ 3c=10\\ c=\frac { 10 }{ 3 }$

Once again. I am not sure and I am open for corrections :)

Angela Fajardo - 5 years, 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$